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Arnaud Fietzke <arnaud.fietzke@provi.de> wrote

> How can i find out wether a point is in an irregular area?  I'm making an
> object which has an irregular area and it must determine if it was clicked
> by the mouse.

If you define the area as a polygon, then the point is "in" the area
if it is on the correct side of each of the sides of the polygon, e.g.

FUNCTION inside(x,y): BOOLEAN;
  BEGIN
    inside = (a*x + b*y < c) AND
             (d*x + e*y > d) AND
             (f*x + g*y < h) AND ...
  END;

The example above has three sides (a triangle).

You can get fancy and allow a polygon to have an arbitrary number of
sides by building a linked-list (or array) of "side descriptors" and a
procedure which steps through the list, checking against each side,
rejecting if it finds any that fail, declaring success if all succeed.

     - Rich